Studies were done or are in progress to accomplish the following regarding sex pheromones in ticks: 1) to isolate, identify and synthesize the sex pheromone(s), 2) to determine the source(s) of the sex pheromone(s) within the female tick's body, 3) to determine whether sex pheromones are produced and/or released only at specific periods of adult life (e.g., during blood sucking, after blood sucking, etc.), 4) to determine how the sex pheromone(s) and synergists, if any, are used in the search for and selection of mates by adult ticks, and 5) to explore the potential for using the synthetic pheromones and detailed knowledge of its role in reproduction to manipulate and disrupt mating success of the tick population. The studies are being done with the American dog tick, Dermacentor variabilis and the Rocky Mountain wood tick, Dermacentor andarsoni, both hard ticks (Ixodidae) and the relapsing fever tick, Ornithodoros Tholozani, a soft tick.